[insert witty title]

It’s a little known fact that most digital cameras can actually see infrared light. You can easily prove this to yourself by pressing buttons on your remote control whilst pointing it at a digital camera. For example, here is my remote control:

This suggests that given a suitable filter it would be possible to do IR photography with a normal digital camera! Luckily most houses do contain such a thing in the form of the negatives that used to be supplied with developed photos*. At the end of the negatives there is often a small black section. This is film that has been completely exposed and then developed.

This bit of the negative blocks out almost all visible light, but lets through IR. To completely block visible light you need two layers of this stuff, which you can then sellotape onto the front of a camera to create a cheap IR viewing device!

I found that in order to get good photographs the camera needed long exposure times (and therefore needed to be supported on a solid base to avoid blurring. Foliage, in particular, looks ghostly since leaves reflect strongly in the IR. Here are a few of my pictures:

Unfortunately light was slipping in from both sides of the filter and I didn’t notice this until it was too late!

_{* maybe they still are, but I don’t know anybody with an analogue camera any more}

Now that I finally have some spare time (Dr. CMB, booya!) I have started doing a few home science experiments again, this post represents the first of these. It’s something that has been on the cards for a long time!

JPS once told me that if you mix ethanol with water then the resulting mixture has a smaller volume than the sum of the volumes of its constituents. According to Wikipedia if you mix equal volumes of water and ethanol the mixture has a volume of only 95.6% of the expected value. After much debate we decided that this must be because “the molecules pack together in a funny way”, but don’t really understand it beyond handwaving and speculation. It’s definitely something outlandish enough that it’d be interesting to see in reality, and today I decided to do so with the aid of a bottle of methylated spirits (95% ethanol) and a measuring jug.

Firstly I did a pretty simple check by taking 250ml of water and placing it into a pint glass, then taking a second 250ml of water and adding it to the glass. The contents of the glass were then poured back into the measuring jug:

The results are pretty unsurprising (250+250=500), but do demonstrate that the measuring jug has a linear scale! The same process was repeated with methylated spirits, just to make sure that nothing funny was going on:

Finally the big test was run. 250ml water + 250ml ethanol = ???

BLOODY HELL! THAT’S MENTAL. Looks to be about 470ml-480ml. Real scientists predict that the actual value should be (500ml * 0.956) 478ml.

Digg this story!

There is something I find very exciting about being able to do science experiments in my kitchen, especially when I manage to demonstrate a fact about nature in a way that both illuminates and entertains. Collected here are ten of my favourite practical science experiments. They have been culled from various places around the web, and a couple of them already form the basis of some of the most popular posts on this blog. I hope you enjoy the list!

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#1 - The Speed of Light With Marshmallow

It is possible to calculate the speed of light using nothing more than a tray of marshmallows in a microwave! Here are step by step instructions

• place marshmallows on a casserole dish, completely covering it with a layer one marshmallow thick
• Put the dish of marshmallows in the microwave and cook on low heat. If your microwave has a rotating plate, remove it. We want the marshmallows to stay still
• Microwaves do not cook evenly and the marshmallows will begin to melt at the hottest spots in the microwave.
• Heat the marshmallows until they begin to melt in four or five different spots. Remove the dish from the microwave and measure the distance between the melted spots. You will find that one distance repeats over and over.
• This distance will correspond to half the wavelength of the microwave, about 6 cm. Now turn the oven around and look for a small sign that gives you the frequency of the microwave. Most commercial microwaves operate at 2450 MHz.

That’s it! All you do now is multiply the frequency by the wavelength. The product is the speed of light.

Example:

Velocity = Frequency * Wavelength

Velocity = 2450 MHz * 0.122 m

Velocity = 2.99 * 10⁸ m/s

Using this technique you can calculate the speed of light to a precision of a few percent!

(link originally from wikihow)

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#2 - Brew Hobowine

There is something very exciting about taking household ingredients, combining them with some science and then drinking the resulting product. Last year I set myself a challenge to make a batch of wine using only ingredients I could beg, borrow or steal.

The experiment wasn’t too successful and I ended up trying to consume something that smelt like the floor of a 3am nightclub. Still, live and learn, eh?

Here are some links to the full process:

Part 1 (Planning: In which the MEPP is introduced)
Part 2 (Implementation: In which we find full instructions on how to brew wine fron things around the house)
Part 3 (More implementation: In which the first batch fails and we try again)
Part 4 (Disaster: In which I fail.)

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#3 - Hero’s Fountain

A Hero’s fountains are really interesting devices, I have seen them described in the following way:

With no electrical cord or batteries or obvious energy input of any kind, a fountain spouts and sprays gracefully

Here is what what one looks like schematically:

Water spurts from the top of the fountain and lands back in the other end. At first glance the fountain really does look like a perpetual motion machine! Here is a DIY version of the same thing:

It’s great fun to build and there are full instructions, pictures and videos in this post

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#4 - Measure Pi With a Pencil

It is easy enough to calculate Pi using only items you probably have in the room with you right now. Here is a step by step guide:

• Find a straight, long thin object. A pencil is ideal, a banana less so.
• mark out on the floor a series of parallel lines (using masking tape unless you don’t mind drawing or painting on your floor), separated by precisely the length of your object
• Get a notepad, make two columns, one saying “crossed” the other saying “missed”
• Throw your item into the parallel lines marked on the floor, if it comes to rest touching a line place a mark in the “crossed” column, otherwise place one in the “missed” column
• Do this until you are bored

You’re done! All you need to do now is multiply the total number of throws by two and divide by the number of crosses. For example if I threw 500 times, and it crossed 320 times, I would calculate 500 * 2 / 320. Via some sort of voodoo they result you get is very close to pi. The more throws you make the closer it will get!

(link originally from wikihow)

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#5 - Fun with Non-Newtonian Fluids

I like non-newtonian fluids, they’re pretty cool things.

To understand what a non newtonian fluid is consider water. At a given temperature the thickness, or resistance to flow (viscosity), of the water is always the same. The same is true for most other everyday fluids. Water is therefore defined as a newtonian fluid

A non-newtonian fluid has a viscosity that depends on the amount of shear force it is experiencing. Think, for example, of silly putty or a mixture of water and cornstarch. If you hit a water-cornstarch mixture it feels solid, but the second you stop stressing it, it flows like olive oil. An incredibly weird feeling.

I remember when I was little getting lots of enjoyment out of making little balls of cornstarch solution then hurling them at the wall so they bounce right off then catching them and watching the solid bouncy ball turn quickly turn into a puddle of liquid.

Here is an awesome video demonstration of the properties of a water-cornstarch mix:

If you haven’t yet tried it, I heartily recommend having a go yourself

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#6 - Extract Your Own DNA

It turns out that it is entirely possible to extract DNA from any living thing using equipment you have lying around in the kitchen. My original plan when researching this experiment was to extract DNA from my own blood and then encase it inside of perspex. It would both make an awesome paperweight and broah the possibility that I could be cloned in some sort of future Jurassic park.

It consists of four main steps: blend up the thing you want to get DNA from and mix it with water; strain so you’re left with water with tiny little bits in it; add enzyme powder (otherwise known as meat tenderizer); pour ethanol (rubbing alcohol) on top of the mixture; the DNA seperates out into the alcohol. Hey Presto! It’s Jurrasic park time.

this site contains much more detailed instructions and pictures.

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#7 - Mixing Liquids

I did not originally believe this was true but I guess in hindsight it makes sense.

Find two half pint glasses and a pint glass. Fill one half pint with water, the other with pure ethanol (methylated spirits, rubbing alcohol). Tip both half pints into the full pint glass. You don’t get the result you would expect! Due to the way that the ethanol and water fit together in the liquid there will be almost a centimeter free at the top of the pint glass!

(link originally from conversation with JPS and wikipedia)

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#8 - Hero’s Engine

One of the simplest and oldest forms of engine is the Hero’s engine. A Hero’s engine consists of a metal container half fille with water. The water is heated to boiling and the steam is channeled out of two pipes of jets, causing the whole apparatus to spin. Rob at Cockeyed made a really nice hero’s engine from a drink can with pinholes in it and some tealights. It is surprising how fast this thing can spin!

(link (and picture) originally from cockeyed.com; pretty much the best site on the internet)

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#9 - Tasty Bacteria

I would try to convince you that this experiment demonstrates how bacteria multiply, but in reality it demonstrates how awesome it is to make yoghurt. Look around the house and find the following objects:

• Powdered Milk: All yoghurt recipes seem to have powdered milk in them. It just sounds pretty gross to me. Ah well, who am I to argue with the experts?
• Honey: I chose german honey from a monastery just outside of Munich. That’s just how classy I am (also the only honey I have sitting on the shelf).
• Active Yoghurt: My yoghurt contains the following bacteria: lactobacillus acidophilus, bifidobacterium, streptococcus, thermophilus. I don’t know what any of that means but it sounds impressive
• Milk: Comes from cows

Using this stuff it is possible to create a good few kilograms of yoghurt. Why anybody would want that much yoghurt is beyond me, but hey! It happened anyway:

Full details and instructions here

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#10 - Liquid Stacking

I guess most of us have seen those really sugary coffees that have cream floated on top:

These work because the amount of sugar in the coffee makes it more dense than the cream. It is possible to take this to the next level and create incredible layered constructions from things around the home. My current record is this stack of six different liquids:

Can anybody beat that?

Instructions available here

I held the first ever liquid stacking world championships last night. There was only one entry so I guess I won by default. In a very profound way I am also the loser.

Despite the lack of cheering hordes (Gemma occasionally came in to check on progress but beyond that it was just me and the spider in the kitchen) I’m going to give a blow by blow recount of this exciting occasion.

I had no real idea how feasable liquid stacking actually is, or how gentle I’d have to be to get it to work so to start with did something that I was pretty sure would work:

On the bottom we have green washing up liquid, followed by white vinegar and then olive oil. I was expecting the vinegar to sit on top of the oil, but it sank straight through and formed a neat layer on between the soap and oil.

I next tried to add a layer of red using some wine. I expected that since alcohol is less dense than water the wine would float on top of the oil but it too just fell straight through! Olive oil is surprisingly underdense.

^{(I am not good at using the camera)}
At least I have determined that wine is less dense than vinegar. Next up I wanted to get a bit more ambitious so I threw this stack away and started afresh using the densest liquid in the entire household: Treacle!. Here is the treacle/washing up liquid system:

Next up I added the oil and vinegar, bringing us back to four levels (here), before trying something new: Soy sauce. The density of the Soy sauce was pretty surprising, it fell all the way through to below the washing up liquid, where it stayed:

The addition of the red wine (I slipped and the red wine got poured a little violently so mixed a bit with the vinegar) brought us up to the current “liquid stacking world record” of six liquids:

If I had any methylated spirits around I’m pretty sure I could have floated that on top of the oil and achieved my original goal of seven liquids.

After seeing how easy this is, I reckon I can stack a dozen liquids. Milk, Thick bleach, rubbing alcohol, honey, coffee, cream, the possibilities are endless. I can’t help but feel that I have tapped into a new source of amusement here.

When I was really little we once ate out at a nice restaurant for some special occasion. After we ate, the waiter bought over a glass of black coffee with cream floating on top. This blew my eight year old mind and even when my dad explained what density was I still couldn’t quite believe it. It felt pretty much like voodoo science.

Anyway, long story short: This memory jumped into my mind the other day and one glass of black coffee, three teaspoons of sugar, and a small amount of single cream later:

Hahahaha! Floating cream. Unfortunately coffee sweetened that much (the sugar increases its density above that of the cream) is really disgusting, but still it is kind of fun to demonstrate little bits of science and it did get me thinking.

After a couple of conversations with Norris and Gemma I think I have invented a new geek-sport: “Extreme Liquid Stacking”. The premise is pretty simple. Look around your house for some liquids. See how many of them you can stack up in a tall, thin container, without them mixing.

There isn’t really any more to the game than that, but I do plan on giving it a try anyway. After a bit of planning with Gemma we’re going to try to stack seven liquids.

^{(If this post makes no sense. Read parts 1, 1.5 and 2)}

Over the past couple of months I’ve had quite a few people ask me what happened to the hobowine project. The truth is that it was a complete disaster and I lost all motivation to finish it off. The reason it failed so terribly is that I am an idiot and my idea of sterilization doesn’t actually kill that many germs. The resulting wine smelt like the inside of a cheap nightclub and tasted like sewage. It made me retch even to smell it. However, I did learn some important lessons from the first attempt and it now feels like the right time to restart the project.

I’ll not bore you with the details of the brew container construction as that was all in part 2, Here is the finished product:

You can clearly see how my “making stuff from bottles and blutack” skills have come along since the fiasco of the first hobowine (detail view here). Virtually everything about this new batch screams class and sophistication, from the sturdily built brewing compartments, to the fact that I didn’t use a single smashed biro in the construction process. The colour coordinated brewing pods (note the synchronisation of the colour of the wine and the colour of the straws — thanks Gemma) really top off the elegance of the whole outfit.

An additional dash of class is added by making wine in three new and ‘exciting’ flavours!

• Outrageous Orange
• Awesome Apple
• Cool Cranberry

I’ll keep you updated!

—–

I was talking to Jim(2) and JCH just now and, inspired by my most recent blog post, asked the question “How many Commodore 64 cassettes would it take to store a copy of windows XP”. The question on its own is poorly defined so I’ll add a few details:

• These are standard C90 audio cassettes (90 minutes long in total)
• We are going to read the data in using only technology from the 1980’s

I’m going to calculate the actual answer tonight and will post the answer soon.

Feel free to take a guess at the actual number in the comments of this post and whoever is closest, without going over, wins a pint of fine ale (or if I don’t know you in real life you just get a hearty huzzah! and the joy of knowing that your wild guess was better than everybody else’s)

After talking to John about people claiming to have created a perpetual motion machine I decided to do a bit of digging around on the internet where I stumbled over these devices, called Hero’s fountains:

_{pictures nabbed from here}

Along with the following descriptions, here:

With no electrical cord or batteries or obvious energy input of any kind, a fountain spouts and sprays gracefully

here:

Hero's fountain derives its name from its inventor, Hero (or Heron), who lived in Alexandria circa 120 B.C.

It is described in his book Pneumatica in which Hero describes a number of appliances invented by himself and by a predecessor named Ctesibuis.”

and here:

A "Hero's Fountain" is a scientific hoax. Basically it is a series of scientific bottles and tubes. When you pour water in the top bowl, it starts to drain out of the tubes, and the end of the line is a "fountain" spigot that spouts the water right back into the top bowl. It looks as it if would run forever (and if you built it right it would run for hours.)"

I love old bits of scientific instrumentation and would kill to own one of these, they look like so much fun. Unfortunately they’re obscenely expensive and after having recently read this article on the home manufacture of one of Hero’s engines I had absolutely no choice but to make one from things lying around the house.

Here is a diagram of a Hero’s fountain:

Considering my DIY skills (pathetic at best) I really wasn’t expecting the fountain to work so didn’t bother making photos of the construction. On a positive note that will save a few minutes in thinking up witty captions for the blog post.

[imagine a really informative and witty "how I built the fountain" paragraph here]

Here is the finished product, constructed from empty bottles, sellotape, a couple of plastic tubes, a broken pen and a lot of blu-tack (what is it with me and making things out of bottles and broken pens?):

In theory, tipping a few hundred milliliters of water into the top of the device should be enough to get it started. Let’s give it a whirl:

Ahaha! It works! A steady stream of water, approximately 3-5cm high. The fountain runs for an entire 15 minutes (!) before losing power due to a few tiny airleaks I couldn’t patch up.

OK so it’s not exactly graceful but what do you expect when the device is held together with blu-tack and sellotape, and hey! I made my very own pressure and gravity driven fountain. I feel like I’m this close now to having a bona fide perpetual motion machine.

I also made a video (with my mobile phone so sorry about the crazy video format). Here is the fountain in action, and here it is again. Sadly by the time of the second video the fountain had developed a slight airleak so its power would decrease quite quickly over time.

There is something very satisfying about sometimes just stopping with all the theory, sitting down with some plastic bottles and just messing about with water, exactly like some greek bloke did millennia ago.

Late edit: Handy household hint. To make things airtight you can cut the end off a balloon and stretch it over leaks. It works really well. All the red, yellow and green bits on my fountain are balloons

If this post makes no sense read part 1 and part 1.5

What with me being a serious scientist and all I thought that before trying to manufacture a gallon of wine I’d do a proof of concept run with a smaller brew, this time about 1.5 liters.

Anyway, with no further ado let’s meet the cast of characters:

From left to right:

• A broken pen: With its career as a writing implement at an end, the noble pen is pushed into service one last time.
• A two litre bottle: Looks odd because I have just washed it out, it is currently drying
• Sugar: Sweet. I actually used sugar provided by our kind sponsors Ikea, Starbucks, Generic Sugar Sachet, and Cafe Nero. Thanks for letting me have those sachets guys.
• Apple Juice: Tasty. I hope
• Yeast: King of brewing

Not pictured: Plastic cup, sellotape, a slice of lemon.

This highly technical plan shows what we are going to be manufacturing:

Step number 1: Burn a small hole in the bottle, using a lighter

Step number 2: Glue and sellotape a broken pen into the hole

Step number 3: Sellotape a disposable plastic cup to the bottle

Congratulations! You have a fully functional, high technology, brewing apparatus! Now to begin with the ingredients. First your yeast needs to be activated. Put one teaspoon of yeast and 5g (one stolen sachet) of sugar into a cup, add some warm water. After a few minutes the mixture will begin to bubble. The yeast is now awake and ready to do battle with the forces of sugar

Mix 150g of sugar into some boiling water. Here is the sugar.

Put the apple juice into the brewing apparatus, add the boiling hot sugar mixture. You may need an adult for this step. On a related note: if you end up in prison and need to mess somebody up real good you can throw a cup of boiling, sugary water into their face. The sugar makes it all sticky and impossible to get off and the boiling water does exactly what you would expect. Just thought I’d share, also it’s much easier than sharpening the plastic handle of a toothbrush into a shiv and gutting them like a fish.

Finally since I’m such a connoisseur or wine, I added a slice of lemon. The zesty freshness of the lemon slice should interact very well with the dull sharpness of the fermented apple juice and I’m sure I’ll end up with an awesome bottle of wine.

Anyway, that’s the current state of play. I have a bottle of sugary apple fermenting away in the airing closet. The airlock is emitting a bubble every two seconds or so, which means at the very least I’m going to get alcohol, even if it does make me retch.

It worked! Somehow I didn’t screw everything up and the final results have the consistency and taste of real yoghurt! Hopefully it will also prove to be exactly as non-poisonous as the shop purchased stuff…

…Only time will tell.

Woooooo!

If the following post makes no sense then read Project Hobowine: Part 1

People keep asking “when are you going to make wine in a bin bag”. My answer has been the same every time: “Soon. I haven’t forgotten about this project*; I’m working on it at this very moment in fact”. The truth of it is that I have definitely not forgotten about the project but that (after a conversation with john) we decided it actually needs to be much more ambitious! One of John’s suggestions that really stood out was:

You are only allowed to use materials that you have begged, borrowed or stolen

Brilliant idea! Sounds like just the thing I need to give a little bit of integrity to this whole, sordid affair! Except I’m not too hot on borrowing so ‘borrowing’ will be replaced with ‘bartering’. I’d like to think of this as the first rule of hobo-club.

Secondly getting the ingredients for wine without any money at all sounds like pretty hard work and I don’t want to waste my time making a bag full of swill! There will be no skimping on ingredients, no tomato ketchup and absolutely no mouldy bread in a sock. Putting this into official words the second rule of wine-club is:

The resulting wine will be made to the best of my ability.

Now what we have here are the foundations of a good challenge. I would, however, like to formalize everything just a little bit:

_________________________________________________________
Hobowine Challenge Official Rules
The final product:

• The total volume of the final product will be at least ___ liters
• The final ABV of the wine will be at least ___ liters
• The flavour of the wine will be _______
• There will be an ‘end of brew’ party at my house for everybody to sample wine (and then go to the pub)

The manufacturing process:

• The only allowable materials shall be either begged, borrowed or stolen from other sources
• The wine will be made to the best of my ability

_________________________________________________________

I would finally add that I’m totally serious about this whole thing. I’m going to try and make wine from free ingredients and will try my best to make it pleasant to drink (I have already thrown away the sugar we found on the floor Saturday night — no need to worry about that ending up in there). I have two final requests:

Firstly I’d like suggestions about what to put into the blank spaces in the ‘official hobowine rules’. Use the comments on this site (you don’t need to register, just click comments below this post), email me, or just suggest it in person.

Secondly I need a lot of sugar so if you’re in a coffee shop or other restaurant that has coffee sachets please grab a couple for me. I’ll not report you to the police, I promise.

_{*Project Hobowine (def): make a drink with a higher mepp than meths}

I like to imagine that if I were homeless then I’d drink a lot of alcohol to make the endless days go a little bit faster and to deaden the blow of every blank faced passer by who doesn’t even acknowledge my existence. Perhaps it would also keep the chill of the winter wind from my bones; for at least a few hours more.

Unfortunately there is a little problem with this plan for perpetual homeless drunkenness… Money is a little tight for the average tramp. It is for this reason that I commisioned a rigorous scientific study into the most efficient way to get trashed.

To begin we need to introduce a brand new statistic, the ‘milliliters of ethanol per penny’ (mepp). mepp is basically a measure of how fucked up something can get you, and how cheaply it can do it. If you’re struggling to understand this concept there is a useful little ditty that will help you: The higher the mepp the more twatted you get.

The ultimate mepp, and the standard by which all other drinks will be judged, is methylated spirits (79p for 500ml, 95% ABV) with a mepp of 6.012658228.

How do standard supermarket drinks stack up against the awesome power of meths? Well, as I’m sure you all know, the only real way to answer this question, like so many others, is with a bar chart*:

Well that certainly is interesting! The White Lightning is a well deserved winner (£2.59 for a 2l bottle, 7.5%ABV). Other drinks, however, did not perform nearly as well as I expected. Tesco value whisky weighed in with a rather disappointing 0.408163265, beaten even by Tesco value gin (0.421348315). Another surprising result is that Tesco value lager (£2.38 for 4×500ml cans, 4%ABV) can hold its own against the incredible fury of the Carlsberg Special Brew (£4.69 for 4×440ml cans, 9%ABV). This means that for those hobos who prefer quantity over ‘quality’ the Tesco beer is a great choice! I like to think that this particular new and exciting result will revolutionise hobo drinking theory over the next couple of decades.

OK enough theory, we don’t need none of that book learnin’ here. There is one question that I know is burning at the soul of every single person reading this article. One question that absolutely must be answered…

Can I make a drink with a higher mepp than Meths? Can I do this in the comfort of my own home? Will I die if I drink it?

Find out in part 2 of this exciting science epic! Coming soon!

_{*If anybody would like me to calculate and tabulate more drinks send me their data. I’ll need hard proof though, not just a vague assurance that a friend of a friend bought a bottle of 50%ABV imported vodka for 47 pence}